A new procedure to prepare slides of metaphase chromosomes of roses

Abstract

To our knowledge, there has been no published technique to produceconsistently high-quality slides of somatic chromosomes of roses (Rosa sp.).Therefore, various pretreatments, fixatives, digestions, stains, andmaceration and squashing methods were tested to identify a procedure toproduce clear, well-spread chromosomes from shoot tips. The best results wereobtained after pretreatment in a mixture of 0.1% colchicine and 0.001 M 8-hydroxyquinoline for 4 h, and fixation in 2 acetone: 1 acetic acid (v/v) with2% (w/v) polyvinylpyrrolidone. The darkest-stained chromosomes were obtainedwith carbolfuchsin staining of air-dried cell suspensions that had beenspread in 3 ethanol: 1 acetic acid (v/v).